As is well known, diesel, gas and steam engines of the reciprocating type typically convert the linear piston motion into rotary motion by utilizing piston(s), connecting rod, and crankshaft. This conversion process obviously creates a substantial piston side load which requires oil lubrication to control friction and wear of the piston skirt and cylinder and a substantial and heavy engine case. To prevent oil breakdown and loss of lubricity the cylinder wall and piston side walls and rings generally are maintained at a temperature that is below a maximum of 350 degrees Fahrenheit. Typically, these engines must incorporate a cooling system that serves to reject at least 25 percent of the total heat energy which is dissipated into the ambient air which energy would otherwise provide shaft horsepower.
As will be described in more detail hereinbelow, the Novotny engine, unlike what is shown in the prior art, floats the piston in the cylinder with a cushion of air by absorbing the side loads that would otherwise load the pistons at locations remote from the piston. Unique to the engine of this invention is the use of curved air feed flexible tubes made from a compliant material that 1) keep the piston ring concentric to the piston and 2) supply air in choked flow (Mach 1) to the integral piston ring depressions to hydrostatically compress the piston ring relative to the cylinder and continuously float the piston and piston ring on pockets of compressed air. The Novotny engine utilizes an accumulator for the purpose of storing base compression air which is raised to a pressure higher than the maximum combustion pressure manifested by the piston operation for use in the lubrication and floating of the piston.
Of interest in this type of engine is U.S. Pat. No. 5,375,567 granted to A. Lowi, Jr. on Dec. 27, 1994, which discloses a two-stroke-cycle engine that requires no cooling and utilizes twin double-harmonic cams that claim to balance reciprocating and rotary motion at all loads and speeds so as to obviate all side loads. As will be more fully detailed hereinbelow, the present invention makes no claim to the ability of operating without lubrication, Although the Novotny engine does not require oil as a lubricant for the pistons as is the case for most piston engines and while it utilizes a quasi-type of twin double-harmonic loads, it utilizes a four bar linkage system to enhance the elimination of the side loads.
Other patents that utilize opposing pistons and harmonic types of cams but do not incorporate a linkage system for minimizing or eliminating side loads are U.S. Pat. No. 2,076,334 granted to E. B. Burns on Apr. 6, 1937, and U.S. Pat. No. 1,788,140 granted to L. M. Woolson on Jan. 6, 1931.
Also disclosed in the prior art are a number of patents that utilize a gas for lubrication rather than oil. For example, U.S. Pat. No. 4,455,974 granted to Shapiro et al on Jun. 26, 1984, utilizes gases generated in the engine to hydrostatically support the piston rings. Similarly, U.S. Pat. No. 4,681,326 granted to I. Kubo on Jul. 21, 1987, utilizes engine gasses to support the piston rings.
U.S. Pat. No. 4,111,104 granted to Davison, Jr. on Sep. 5, 1978, utilizes engine gases to support the piston and U.S. Pat. No. 3,777,722 granted to K. W. Lenger on Dec. 11, 1973, support a ringless piston with air for reducing friction.